| HS Code | 758414 |
| Productname | SELVOL Polyvinyl Alcohol 205 |
| Chemicalname | Poly(vinyl alcohol) |
| Casnumber | 9002-89-5 |
| Appearance | White to off-white granular powder |
| Degreeofhydrolysis | 87.0 - 89.0 mol %, partially hydrolyzed |
| Viscosity | 5.0 - 6.0 mPa·s (4% aqueous solution at 20°C) |
| Ph | 5.0 - 7.0 (4% aqueous solution) |
| Ashcontent | ≤ 0.5% by weight |
| Volatilecontent | ≤ 5.0% by weight |
| Averagemolecularweight | Approximately 35,000 |
| Solubility | Soluble in water; insoluble in ordinary organic solvents |
| Specificgravity | Approximately 1.27 |
As an accredited SELVOL Polyvinyl Alcohol 205 factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Supplied as a free-flowing white powder in 25 kg multi-ply paper bags with a polyethylene liner for safe handling and storage. |
| Container Loading (20′ FCL) | 20′ FCL container loading of SELVOL Polyvinyl Alcohol 205: secure palletized bags, protect from moisture, and ensure safe, stable transport. |
| Shipping | SELVOL Polyvinyl Alcohol 205 is supplied as a white granular powder in sealed multi-wall paper bags. It is non-hazardous under transport regulations, but handle to minimize dust. Keep dry and protected from moisture during transit. Ship via standard covered freight, avoiding extreme heat and direct contact with oxidizing materials. |
| Storage | Store SELVOL Polyvinyl Alcohol 205 in a cool, dry, well-ventilated area away from heat, open flames, and strong oxidizers. Keep containers tightly sealed to prevent moisture absorption and contamination. Avoid generating dust; use appropriate ventilation. Protect from physical damage and store out of direct sunlight. Follow manufacturer’s recommendations for shelf life and handling. |
| Shelf Life | Shelf life: 2 years when stored in original, tightly sealed containers in cool, dry conditions away from moisture and extreme heat. |
On high-speed paper and paperboard machines where rod-metered film presses run at 800–1,500 m/min, SELVOL Polyvinyl Alcohol 205 functions as a low-viscosity surface-sizing co-binder rather than a primary starch replacement. The grade is pre-dissolved at 10–12 % solids in a 90–95°C jet cooker or in a separate atmospheric slab tank, then metered into oxidized corn or tapioca starch at 5–15 kg dry PVOH per 100 kg dry starch. Final size-press solids are held at 4–8 % depending on base-sheet porosity and target holdout; dry size-press add-on is typically 0.3–1.2 g/m² per side when measured gravimetrically. The low ash content of the grade, below 0.5 %, limits insoluble deposits on size-press rolls during long campaigns. For food-contact grades, the finished paper or paperboard must be tested under FDA 21 CFR 176.170 and FDA 21 CFR 176.180 using aqueous and fatty food simulants, and under EU 1935/2004 with migration verification per EN 1186-1. Surface quality is assessed by ISO 535 Cobb60, ISO 8791-4 Parker Print Surf roughness, and IGT dry pick resistance per ISO 3783; offset and inkjet converters commonly specify Cobb60 values below 25 g/m². The downstream production sequence includes size-press application, infrared or air-float drying to 4–6 % sheet moisture, and reel calendering. Terminal products include envelope papers, lightweight coated base stock, inkjet substrates, SBS folding carton board, and release liner base papers.
The reactor charge for semi-batch emulsion polymerization of vinyl acetate, vinyl acetate-ethylene, or acrylic esters contains SELVOL Polyvinyl Alcohol 205 as an aqueous solution at 10–20 % solids, with the dry protective colloid level between 2.0 wt% and 6.0 wt% based on total monomer. The 87–89 mol% hydrolysis range leaves sufficient residual acetate groups to reduce aqueous surface tension and to promote grafting onto growing polyvinyl acetate chains, while the 5.2–6.2 cP viscosity at 4 % solids keeps reactor viscosity low enough for efficient heat transfer in a baffled glass-lined or stainless steel reactor. A pitched-blade turbine with tip speed of 2.0–3.5 m/s is used; higher shear can reduce protective colloid adsorption and increase coagulum formation. Redox initiation with hydrogen peroxide and sodium formaldehyde sulfoxylate or tert-butyl hydroperoxide and sodium metabisulfite is fed over 180–240 min at 60–75°C. Vinyl acetate and ethylene are fed as delayed streams, keeping free monomer below 0.5 wt% during polymerization, measured by capillary GC per ISO 13741-1. The resulting dispersion is tested for solids per ISO 3251, Brookfield viscosity per ISO 2555, pH per ISO 976, and particle size by dynamic light scattering per ISO 22412. Borate-containing buffer salts are avoided in this system because borate-diol complexation with the partially hydrolysed PVOH backbone increases viscosity and can induce coagulum formation. For wood adhesive formulations, wet and dry bond strength must meet durability class D2 or D3 under EN 204. For food packaging adhesives, the dispersion must comply with FDA 21 CFR 175.105 and, where the finished article is a plastic food-contact material, with EU 10/2011 migration limits. Terminal products include polyvinyl acetate homopolymer and VAE copolymer dispersions for paper converting adhesives, nonwoven binders, interior paints, wood glues, and laminating adhesives.
Sizing formulations for spun polyester, polyester/cotton, and ring-spun cotton warps use SELVOL Polyvinyl Alcohol 205 as a low-viscosity film former that can be combined with oxidized starch or modified starch and an acrylic co-binder without raising size-box viscosity beyond 8–14 s Zahn cup #3 at 90°C. The recommended addition is 4–10 % of total size solids, with size-box solids from 6 % to 12 % depending on yarn hairiness and loom speed. Wet pick-up at the squeeze rolls is adjusted to 8–14 % dry add-on by weight of yarn; add-on below 6 % is avoided because insufficient film continuity increases stops caused by warp breaks in air-jet filling insertion. The size is cooked in a jet cooker at 110–130°C for starch gelatinization and held in the size box at 85–95°C. Drying is carried out over Teflon-coated cans at 110–140°C surface temperature to a residual moisture of 4–6 %, followed by splitting at the lease rods. Sized yarn strength and elongation are measured by ASTM D2256, yarn hairiness by ASTM D5647, and abrasion resistance by the Zweigle G567 loom simulation. Textile compliance is governed by the Zero Discharge of Hazardous Chemicals Manufacturing Restricted Substance List and, for export, by OEKO-TEX Standard 100 Annex 4 criteria for residual volatile organics. Terminal products include woven apparel fabrics, workwear, bedsheet fabric, and lining fabric produced on air-jet and rapier looms at weft insertion rates above 1,200 m/min.
Water-soluble film produced with SELVOL Polyvinyl Alcohol 205 as the sole resin exhibits lower tensile strength and higher blocking tendency than film based on medium or high viscosity grades; therefore the 205 grade is not recommended as the sole film-forming resin for pouch packaging above 50 parts per 100 parts total PVOH. In blended formulations, 20–50 parts of SELVOL 205 replace an equivalent dry weight of a medium-viscosity partially hydrolysed grade of 15–25 cP to reduce solution viscosity and to shift cold-water dissolution time downward. The casting formulation contains 100 parts total PVOH, 10–20 phr glycerol, 5–10 phr sorbitol or trimethylolpropane, 0.3–0.8 phr nonionic defoamer, and water to a total solids of 18–25 %. Dissolution is performed in a scraped-wall or jacketed high-shear mixer at 80–95°C for 45–90 min, followed by vacuum deaeration at −0.08 to −0.09 MPa. The deaerated solution is cast through a slot die onto a chrome-plated belt or PET carrier and dried in stages from 70°C to 110°C to a residual moisture of 6–12 %. Mechanical properties are tested per ISO 527-3; cast film tensile strength is typically 20–35 MPa and elongation at break 200–400 % depending on plasticizer content and moisture. Dissolution is measured by the in-house paddle or jar method at 10–20°C; detergent unit-dose pouches must survive 30–60 s dry handling and release within 60 s in wash liquor. Detergent formulations containing high borate salt concentrations can reduce film solubility through borate-diol complexation; compatibility testing is therefore required before converting. Biodegradation is evaluated by ISO 14851. Pre-drying is required before thermoforming when ambient relative humidity exceeds 60 %; roll blocking is controlled by storing film at 20–25°C and 35–50 % RH. Food-contact plastic articles must comply with EU 10/2011 where a food-contact approval exists; detergent and agrochemical sachets are assessed under UN GHS product classification. Terminal products include detergent unit-dose pouches, water-soluble agrochemical sachets, embroidery topping film, and transfer-printing carrier film.
Envelope back-seam and window-patch remoistenable adhesives are compounded with SELVOL Polyvinyl Alcohol 205 at 10–30 % dry weight of the final adhesive film, alongside 20–40 % dextrin, 5–15 % urea or glycerol as humectant, and 0.5–2.0 % preservative. The dry blend is dispersed at 30–45 % solids and applied by doctor roll or slot die at 15–30 g/m² wet film weight on envelope stock; drying is carried out at 60–90°C to a tack-free film. Rewetting compatibility is measured with a recycled paper lap bond test after 3–5 s water application; dry adhesion is assessed by ASTM D1876 T-peel or ISO 11339. Borated dextrin grades must be avoided when the formulation contains more than 15 % PVOH because borate ions crosslink the 1,3-diol units of polyvinyl alcohol and create an irreversible viscosity rise in the coating pan. For food contact, the dried adhesive layer must comply with FDA 21 CFR 175.105 and with 21 CFR 176.170 if the adhesive is used on paperboard intended for direct food contact. Terminal products include remoistenable envelopes, window patch film adhesives, paper labels, trading stamp sheets, and paper tube winding adhesives.
In technical ceramic body preparation, SELVOL Polyvinyl Alcohol 205 is used as a temporary organic binder at 0.5–2.0 wt% based on dry ceramic solids, introduced as a 5–10 % aqueous solution into an alumina or zirconia slurry already containing 0.3–0.8 % ammonium polyacrylate dispersant. The slurry is milled to a median particle size of 0.5–2.0 µm and spray-dried with a rotary atomizer at inlet air 200–250°C and outlet air 90–110°C. The resulting granules contain 1–3 % residual moisture and retain sufficient binder for dry pressing at 50–200 MPa in a hydraulic press. Green strength is measured as three-point flexural strength per ASTM C1161 or EN 843-2; values below 1 MPa generally indicate overwet granules or binder migration to granule surfaces, while values above 3 MPa may require longer thermal debinding. Debinding is conducted in air or nitrogen from 350°C to 600°C over 4–12 h, with the heating rate below 1°C/min between 150°C and 350°C to avoid carbon residue from incomplete oxidation. Compliance for electronic ceramics includes RoHS Directive 2011/65/EU Annex II substance restrictions; for sintered parts used in food-contact applications, the finished article must satisfy applicable national food-contact legislation and, if an organic coating or plastic component remains, EU 10/2011 migration limits. Terminal products include alumina substrates, wear plates, piezoceramic blanks, multilayer ceramic capacitor bodies, and technical ceramic components formed by uniaxial dry pressing.
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SELVOL Polyvinyl Alcohol 205 is a partially hydrolysed polyvinyl alcohol supplied as a free-flowing granular solid under CAS RN 9002-89-5. The standard analytical profile places the degree of hydrolysis at 87.0–89.0 mol% and the viscosity of a 4.0 wt% aqueous solution at 20.0 °C at 5.2–6.2 mPa·s. Volatile matter is controlled to ≤5.0 wt%, residue on ignition to ≤0.5 wt%, and solution pH to 4.5–6.5 when tested in accordance with JIS K6726. The grade falls into the low-to-moderate molecular weight partial hydrolysis class, with the residual acetate fraction providing cold-water solubility and interfacial activity that are not available from fully hydrolysed polyvinyl alcohol.
| Parameter | Specification | Analytical basis |
|---|---|---|
| Degree of hydrolysis | 87.0–89.0 mol% | JIS K6726 |
| Viscosity, 4.0 wt% aqueous solution, 20.0 °C | 5.2–6.2 mPa·s | JIS K6726 |
| Volatile matter | ≤5.0 wt% | JIS K6726 |
| Residue on ignition | ≤0.5 wt% | JIS K6726 |
| pH of 4.0 wt% solution | 4.5–6.5 | JIS K6726 |
The 87.0–89.0 mol% hydrolysis window leaves 11.0–13.0 mol% residual acetate groups. These substituents inhibit the close packing and interchain hydrogen bonding responsible for the high crystallinity of fully hydrolysed PVOH. Under low-shear stirring at 300–500 rpm, a 4.0 wt% dispersion in water at 20.0 °C reaches visual clarity without the 80–90 °C cook required for fully hydrolysed grades of similar viscosity. Dissolution rate is particle size dependent; powder passing a 60 mesh screen disperses without lump formation, whereas oversized granules can form gel skins that require a high-shear mixer or extended agitation.
Storage in warehouse conditions above 60% relative humidity increases moisture uptake and reduces dry-flow properties. Bagged material should remain sealed until use, and powder handling hoppers should be purged with dried air. Solutions at 10.0–12.0 wt% solids prepared at 60 °C are typically stable for 48–72 h at 20–25 °C when protected with an isothiazolinone biocide; published data for this specific configuration is limited, and plant preservative loading should be confirmed by microbial challenge testing.
The specification viscosity is read at 20.0 °C on a rotational viscometer with a UL adapter. Because PVOH solutions become pseudoplastic above 6 wt%, measurement at 4.0 wt% reduces shear-history dependence. A temperature deviation of ±0.5 °C changes apparent viscosity by approximately 2–3%; therefore, the cup is held in a circulating bath rather than left on the bench. Plant verification uses a sample dried to constant weight at 105 °C, dissolved under low-shear agitation for 1–2 h at 60–70 °C, held at 20.0 °C for 1 h, and filtered through 200 µm mesh before measurement. Filtration removes undissolved gel skins that otherwise increase apparent viscosity by obstructing the spindle gap.
Above 10 wt%, the solution is pseudoplastic. A single-point Brookfield value at 60 rpm is therefore insufficient for equipment sizing in coating and size-press circuits; a cone-plate sweep from 0.1 s⁻¹ to 100 s⁻¹ is preferable.
Production-scale solution make-down uses a venturi eductor or high-shear disperser to wet the powder into water at 20–30 °C, followed by a jacketed holding tank at 60 °C for 30 min. The solution is then passed through a 100–200 µm bag filter to remove gel skins and foreign particulates before metering into the process. Failure to filter at this stage produces fisheyes in cast film and lumps in adhesive coatings; on a 2,000 L batch these defects can require 4–6 h of downstream rework.
In vinyl acetate homopolymer and vinyl acetate-ethylene emulsion polymerisation, SELVOL Polyvinyl Alcohol 205 is charged as a pre-dissolved protective colloid at 8.0–12.0 wt% solids from a jacketed feed tank held at 55–65 °C. Batch recipes typically use 3.0–6.0 parts per hundred parts monomer, with initiation by sodium persulfate or a redox couple at 55–85 °C depending on reactor pressure. The partial hydrolysis range provides higher interfacial activity at the vinyl acetate-water interface than fully hydrolysed PVOH at equivalent solution viscosity. On 5,000–20,000 L production reactors, this lowers coagulum formation and produces a narrower final particle size distribution measured by dynamic light scattering after 200 µm filtration; the exact magnitude is site-specific and published data for this specific configuration is limited.
The most common manufacturing failure is cold feedstock entering a colloid transfer line below 40 °C, which creates gel specks that can pass into the finished emulsion. Transfer piping should be traced and held at 50–60 °C. Agitator tip speed should be kept between 1.5 m/s and 2.5 m/s; shear-induced destabilisation at higher tip speeds can raise coagulum, particularly in continuous stirred-tank reactors where the protective colloid layer is not rebuilt as rapidly as in batch operation.
Substitution into cast film or barrier coatings requires recalculation of moisture resistance and tensile load. Films conditioned at 23 ± 2 °C and 50 ± 5 % relative humidity exhibit lower tensile strength and higher elongation than fully hydrolysed PVOH of equivalent 4.0 wt% viscosity when tested under ASTM D638-14; published data for this specific grade is limited, so laboratory correlation with target coating weight is necessary. Water absorption measured by ASTM D570-98 after 24 h immersion is higher because the residual acetate phase is more hydrophilic than fully hydrolysed domains. The product is not used as an isolated high-moisture barrier layer unless crosslinked or blended with a fully hydrolysed grade at 20–40 wt% of total PVOH.
For water-resistant adhesive films, glyoxal addition at 0.5–2.0 wt% of dry PVOH reduces cold-water sensitivity but shortens pot life to 4–8 h at 25 °C. Amine-based catalysts should be avoided in glyoxal-crosslinked systems because they can accelerate premature gelation. The lower tensile modulus of 205 relative to fully hydrolysed PVOH improves cold-water removability, which is useful for temporary protective coatings but becomes a limitation in structural adhesive service.
Differential scanning calorimetry of the partially hydrolysed film shows a lower glass transition temperature than fully hydrolysed PVOH; the exact value depends on residual moisture, and conditioning should follow ISO 291.
Compared with a lower-viscosity partially hydrolysed grade such as SELVOL Polyvinyl Alcohol 203, SELVOL 205 generates higher solution viscosity and higher film tensile at equal solids. Compared with a fully hydrolysed grade of similar viscosity, it offers lower dissolution temperature, higher water sensitivity, and higher protective-colloid efficiency in vinyl acetate polymerisation. The selection between these types is therefore defined by the acceptable trade-off between cold-water removability and water resistance.
| Comparative property | SELVOL 205 | Lower-viscosity partially hydrolysed PVOH | Fully hydrolysed PVOH of similar viscosity | Test basis |
|---|---|---|---|---|
| Degree of hydrolysis | 87.0–89.0 mol% | 87.0–89.0 mol% | 98.0–99.0 mol% | JIS K6726 |
| 4% solution viscosity at 20 °C | 5.2–6.2 mPa·s | 3.5–4.5 mPa·s | 5.0–7.0 mPa·s | JIS K6726 |
| Minimum dissolution temperature | 20–25 °C | 20–25 °C | 80–90 °C | Visual clarity after 30 min stirring |
| Water absorption | Higher than fully hydrolysed | Higher than fully hydrolysed | Lower | ASTM D570-98 |
| Protective colloid efficiency in vinyl acetate polymerisation | Higher | Similar | Lower | Coagulum residue on 200 µm screen |
Surface sizing of fine paper and paperboard is typically run at 4.0–8.0 wt% solids, cooked at 85–90 °C for 30 min, and applied at 55–60 °C through a puddle or metering size press with nip pressure 0.4–0.6 MPa. SELVOL 205 forms a size-press solution that can be washed from rolls with cold water at 20–25 °C; fully hydrolysed grades require hot-water cleanup above 70 °C. With cationic starch at pH 5.5–6.5, the solution shows moderate penetration into the sheet. At addition levels above 8 wt%, viscosity should be corrected using rotational viscosity data rather than refractive index solids because the latter does not track batch-to-batch hydrolysis variation.
In cotton and polyester/cotton warp sizing, 8.0–12.0 wt% solids are cooked with steam to 90 °C and applied at 55–65 °C on a slasher equipped with a squeeze nip. Low add-on of 6–10% dry weight on warp yarn is typical because the low-to-moderate molecular weight limits solution viscosity and permits size penetration into the yarn core. Yarn tensile retention after sizing is evaluated by ASTM D2256; published data for this specific configuration is limited, and a split-warp trial is recommended before conversion from acrylic or starch sizes. The partial hydrolysis permits desizing in cold water at 20–25 °C, whereas fully hydrolysed grades require oxidative or hot-water desizing at 70–80 °C. The main operational limitation is low film strength on continuous-filament polyester at high loom speeds; blending with a higher-viscosity partially hydrolysed grade is used where weaving performance requires it.
Incoming quality control should include moisture, 4% solution viscosity, pH, and ash. Moisture is used to correct solids in compounding; using as-received weight without correction can shift final solids by up to 5% relative, equivalent to 0.4 wt% absolute at an 8 wt% target solids. Viscosity is the primary molecular weight index because the supplier does not publish a weight-average molecular weight specification. Blended lots should be dry-mixed for 15–20 min in a ribbon blender before solution preparation to reduce batch-to-batch viscosity drift.
Water-remoistenable adhesives for labels and tapes use 12–20 wt% solids with plasticiser addition of 5–15 wt% on dry PVOH, typically glycerol or sorbitol. The partial hydrolysis surface activity gives rapid rewetting at 20–30 °C, but bond shear at 70% relative humidity is reduced by moisture plasticisation. Borate-containing tackifiers should be avoided because reversible gelation builds viscosity without improving dry adhesion. For packaging adhesive compliance, the compound should be checked against 21 CFR 175.105 or 21 CFR 176.170 as appropriate for the substrate. Aqueous formulations stored more than 48 h require a preservative; the grade does not provide antimicrobial function.
